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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin-top: 0;
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        #tips{
            text-align: center;
            position: absolute;
            height: 100%;
            width: 100%;
            background-color: rgba(90, 90, 90, 0.6);
            z-index: 888;
            display: block;
        }
        #main{
            height: 500px;
            width: 100%;
            background-color: rgba(56,56,56,0.7);
            /* z-index: 2000; */
        }
        #iframeInfo{
            position: absolute;
            width: 100%;
            height: 400px;
            /* background-color: rgba(90, 90, 90, 0.7); */
            top: 0;
            /* z-index: 999; */
        }
    </style>
</head>
<body>
    <div id="main"><p style="text-align: center;color:#fff;">这是主页面的内容</p></div>
    <div id="iframeInfo">
        <iframe src="./18.0-遮罩层1.html" frameborder="0" height="300" width="700" id=""></iframe>
    </div>
    <!-- <div id="tips"></div> -->
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
    <script>
        $("#main").on('click', function(){
            console.log(window.parent.document.getElementById("main"));
        })
    </script>
</body>
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